VACCINE TITERS

Currently at Cape Horn Veterinary Associates, we allow titer testing to waiver out of the canine DHPP and feline FVRCCP vaccines. Vaccination titers do not 100% confirm whether a pet will be fully protected from a vaccine when faced with natural exposure, however, significant correlation can be inferred. Ideally, titers can be performed at least 1 month after the last vaccine in the puppy/kitten series and/or at 1 year of age or greater. Titers should be run in 1–3 year intervals (we will make that decision based on your pet’s age, health, and risk status) in order to track your pet’s immune status. Should your pet fall under “adequate” levels for any component of the vaccine, a booster vaccine should be given at age-appropriate intervals.

There are currently no applicable titer tests to waiver out of canine Lyme, canine Leptospira, canine bordetella, or feline Leukemia vaccines. These vaccinations are elective and will be administered only on a case-by-case basis to at-risk pets.

While we can titer rabies vaccines to check protective levels, Pennsylvania law still requires re-vaccination despite titer-able levels. The only time a rabies vaccine waiver may be provided is if the animal suffers from a severe reaction to the vaccination or is in such poor health status that the vaccination could become life threatening to the animal. A copy of this waiver must be provided annually with a physical examination and kept on file with the Pennsylvania Department of Health, otherwise the pet will be subject to court-ordered euthanasia and testing should a bite or exposure occur. From time to time we may need to perform a rabies titer for pet export to Hawaii or rabies-free nations worldwide.

We have recently contracted with Kansas State University to do all of our vaccine titers at a discounted cost to our clients. KSU is part of an ongoing vaccine titer study with certain breeds and certain vaccines and are developing a scientific and numerical database in order to track patient titers. It takes approximately 7–10 days to receive results. If a vaccine titer is needed sooner, we can submit to our regular diagnostic laboratory and turn-around time is 2–3 days; however, the cost is higher.

From Kansas State University’s Diagnostic Laboratory in regard to vaccination titers:

“Vaccine-induced immunity is a multifaceted process involving antigen processing, humoral immunity, cell mediated immunity, local immunity and cell memory. Predicting whether a patient is protected against a disease based solely on a single serum titer is a gross oversimplification of this complex immune process. However, despite the drawbacks, the use of serum titers in making logical and informed vaccine-related decisions is gaining some popularity, especially in animals with histories of a previous vaccine reaction, in those individuals prone to allergic reactions, or in those specific cases where concerns of 'over vaccinations' persist.

When interpreting any serum vaccination titer, you must take the following key points into consideration:

Titer results will vary depending on the laboratory and testing methodology used.

Even among the experts, there is no clear consensus on exactly what titer is considered protective for each specific disease.

Titers measure the patient’s immune status at a single point in time and may not necessarily reflect the patient’s future immune status one month or one year later.

A positive titer will protect against development of the clinical signs of that disease in the patient; however, it may not prevent the patient from becoming infected or even transmitting the agent.

Titers only measure circulating humoral antibodies and not cell-mediated immunity, local immunity, cell memory or the anamnestic response to a viral challenge. Therefore, patients with low titers may in fact be protected."

Click here for more information on Kansas State University’s titer testing.